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    tungsten (W)

    tungsten filament
    A hard, brittle, corrosion-resistant, silvery-gray metallic element that has the highest melting point of any metal and the second highest of any element (after carbon); it also has the lowest vapor pressure of any metal. It is a transition element in group VIB of the periodic table.

    Tungsten is extracted from wolframite (named after the German wolfram for the element), scheelite, and other minerals. Tungsten and its alloys are used in high-temperature structural materials, electrical elements, especially light filaments, and instruments requiring thermally compatible glass-to-metal seals. When added to steel, tungsten increases its strength. It is alloyed other metals to make "superalloys" which have special physical properties of high strength and heat resistance. Some of the applications for such superalloys are in turbine engines for jet aircraft and energy generation. Other alloys bearing tungsten are used for armaments, heat sinks, radiation shielding, weights and counterweights, wear-resistant parts and coatings.

    Tungsten is relatively inert, and resembles molybdenum. Tungsten carbide is used to make cutting tools and wear-resistant tools for metalworking, drilling for oil and gas, mining, and construction.

    Tungsten was discovered in 1758 by Axel Fredrik Cronstadt; in 1781 Carl Wilhelm Scheele isolated a tungsten oxide, and in 1783 the Spanish chemists (and brothers) Fausto and Juan Jose de Elhuyar, working in Vergara, first separated tungsten from the mineral wolframite. The name comes from the Swedish tung sten, meaning "heavy stone".


    atomic number 74
    relative atomic mass 183.85
    electron configuration 1s22s22p63s23p63d104s24p6
    4d105s25p64f145d46s2
    melting point 3,410°C (6,170°F)
    boiling point 5,927°C (10,701°F)
    relative density 19.3 (at 20°C)


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